1. Field of the Invention
The invention relates to the field of actuators and, in particular, to an actuator for opening and closing aerodynamic control surfaces and doors on an aircraft and the like.
2. Description of Related Art
Actuating control surfaces and doors on aircraft is typically accomplished by means of a linear actuator mounted to the airframe and coupled by a linkage system to control surface or door. However, in some applications space prevents their usage. Thus a hydraulically or electrically operated rotary actuator is used. But these are generally large and require gear reduction systems.
Rotary actuators with helical cam guides have been used in various applications. For example, published patent application US 2003/0015048 A1 Transmission For A Stabilizer Arrangement For A Motor Vehicle Chassis by R. Schmidt, et al. discloses a screw drive with cams that engage two concentric sleeves with helical slots for rotating the sleeves in opposite directions. They have been used in door locks. However, no known prior art actuator system has converted the linear movement of output member of a hydraulic or pneumatic linear to rotate a door or in a plane perpendicular to the movement of the output member.
Thus, it is a primary object of the invention to provide an actuation device for moving a structure such as a door from one position (closed) to a second position (open).
It is a still further object of the invention to provide an actuator system for converting the linear movement of output member of a hydraulic or pneumatic linear actuator to rotate a door or the like in a plane perpendicular to the movement of the actuator.
It is another object of the invention to provide an actuation device for moving a structure such as a door from one position (closed) to a second position (open) using helical cams.